Card reader terminal with external contactless antenna

ABSTRACT

Techniques for performing secure contactless payments are disclosed. An example apparatus includes an external contactless card reader, including a first short-distance communication antenna, connected to a card reader terminal using a feed line. The first short-distance communication antenna is configured to convert an electromagnetic signal including data received from a contactless payment card into an analog signal and is not configured to digitize the analog signal. The card reader terminal includes a short-distance receiver circuit and a secure controller, both located within a secure area, and a second short-distance communication antenna, wherein the first and second short-distance communication antennas are connected via separate paths to the short-distance receiver circuit. An example method includes receiving an electromagnetic signal including card data via a short-distance communication antenna in an external contactless card reader, converting the electromagnetic signal into an analog signal and transferring the analog signal to a card reader terminal.

TECHNICAL FIELD

The disclosure pertains to the field of secure electronic payments. Moreparticularly the disclosure relates to a secure arrangement forperforming secure contactless payments, with an external contactlesscard reader.

BACKGROUND

In today’s commerce, merchants often utilize so called point-of-sale,POS, devices, including mobile POS, mPOS, devices to process financialtransactions, in particular credit card payments.

POS terminals are connected, usually with wires, to a cash register andto an internet connection. Some terminals process chip cards. In suchterminals a card is inserted into the terminal and the user enters aPersonal Identification Number, PIN, on a keypad of the terminal. Otherterminals process magnetic stripe cards. In such terminals the card isswiped through a slot.

Recent POS terminals also provide support for payments using a shortdistance wireless technology such as Near Field Communication, NFC, forcommunicating with the credit card. NFC, allows for wirelesscommunication between two devices in close proximity to each other.

In the contactless solutions, the POS terminal is equipped with ashort-distance communication antenna configured for converting anelectromagnetic signal comprising card data, received from a contactlesspayment card, into an analogue signal.

The antenna, which defines the “tap zone”, where the user needs to “tap”his or her credit card, is traditionally placed on the card readerdevice e.g. a POS terminal. Generally POS terminals have a delimitedarea where a customer must tap their card or device to achieve asuccessful read. This identified area is referred to as the tap zone orlanding zone. The tap zone must be a clearly distinguishable area on thePOS terminal and the contactless symbol must be placed in the center ofthe tap zone at the terminal. The Contactless Reader (or PCD) is e.g.part of a cardholder-facing display that includes visual statusindicators (such as lights or LEDs) and a beeper.

However, a tap zone located on the card reader may be difficult toreach. It may also be difficult for a user to understand where he/sheshould tap his/her card, as the antenna may for security orimplementation reasons, be located such that the center of the tap zoneis e.g. in the center of the key board. Hence, there is a need forimproved solutions, where usability of contactless payments is improved.

SUMMARY

An object of the present disclosure is to provide a wireless devicewhich seeks to mitigate, alleviate, or eliminate one or more of theabove-identified deficiencies in the art and disadvantages singly or inany combination and to provide a solution wherein usability is improvedwhile keeping security and cost at a reasonable level.

This object is obtained by a secure arrangement for performing securecontactless payments comprising a card reader terminal, an externalcontactless card reader and a feed line. The card reader terminalcomprises a secure controller configured for performing financialtransactions, wherein the secure controller is located in a secure areawithin the card reader terminal and the external contactless card readercomprising a short-distance communication antenna configured forconverting an electromagnetic signal comprising card data, received froma contactless payment card, into an analogue signal. The feed lineconfigured for transferring the analogue signal between the externalcontactless card reader and the card reader terminal. Furthermore, thesecure area in the card reader terminal comprises an A/D converter fordigitizing the analogue signal to a digital signal that can be processedby the secure controller.

The secure arrangement provides for a solution where it is convenientfor the customers to make a payment, as the merchant may move the tapzone to a desirable position. Today, the contactless antenna is part ofthe card reader and often it is less evident to the customer where toplace the card or device. It might not even be clear to the customerthat it is possible for them to pay using a contactless card or device.By connecting the external antenna to the card reader with a cable, theanalogue signal is kept all the way to a secure area in the card reader.Thereby, no additional exposure of the card data is caused by the securearrangement. This makes the solution very cheap as all the additionalsecurity related aspects when converting the data into digital form maybe omitted.

According to some aspects, the external contactless card readercomprises at least one antenna matching circuit positioned between theshort-distance communication antenna and the A/D converter. The antennamatching circuit is configured for matching the frequencycharacteristics of the short-distance communication antenna withfrequency characteristics of the feed line, or with frequencycharacteristics feed line in combination with frequency characteristicsof a connection point of the feed line in the card reader terminal.Thereby power transfer may be maximized and effects of the load aremitigated.

According to some aspects of the proposed disclosure, the secure area ofthe card reader terminal comprises a short distance receiver circuitryand wherein A/D converter is located inside the short distance receivercircuitry.

According to some aspects, the short-distance communication antenna inthe external contactless card reader is a first short-distancecommunication antenna and wherein the card reader terminal comprises asecond short-distance communication antenna and wherein the first andsecond short-distance communication antennas are both connected to theshort distance receiver circuitry. The solution enables hardware to bereused by both the short distance antennas.

According to some aspects, the card reader terminal comprises a switcharrangement configured to connect at least one of the first and secondshort-distance communication antennas to the receiver circuitry. Thusthe merchant may select between the antennas in a simple way.

According to some aspects, the card reader terminal comprises at leastone antenna matching circuit for matching frequency characteristics ofthe second short-distance communication antenna with frequencycharacteristics of a connection point in the card reader terminal and/orfrequency characteristics of the feed line, or frequency characteristicsof the feed line in combination with frequency characteristics of aconnection point of the feed line in the external contactless cardreader, with the frequency characteristics of a connection point of thefeed line in the card reader terminal.

According to some aspects, the secure area is tamper proof. Having thesecure area tamper proof results in e.g. that secure data stored thereincannot be accessed by an unauthorised person.

According to some aspects, the external contactless card readercomprises an electromagnetic shield for protecting its internalcircuitry, including at least the short-distance communication antenna,from magnetic and/or electromagnetic interference. The electromagneticshield may comprise a metallic layer shielding the short-distancecommunication antenna from an underlying surface and, optionally, aferrite layer arranged between the antenna and the metallic layer tooptimize operation of the external contactless card reader in metalenvironments.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing will be apparent from the following more particulardescription of the example embodiments, as illustrated in theaccompanying drawings in which like reference characters refer to thesame parts throughout the different views. The drawings are notnecessarily to scale, emphasis instead being placed upon illustratingthe example embodiments.

FIG. 1 illustrates a contactless payment.

FIG. 2 illustrates a payment using a card reader terminal equipped withan external short-distance communication antenna.

FIG. 3 illustrates a secure arrangement according to some embodiments ofthe invention.

FIG. 4 illustrates schematically a side view of an externalshort-distance communication antenna and its internal components.

DETAILED DESCRIPTION

Aspects of the present disclosure will be described more fullyhereinafter with reference to the accompanying drawings. The apparatusdisclosed herein can, however, be realized in many different forms andshould not be construed as being limited to the aspects set forthherein. Like numbers in the drawings refer to like elements throughout.

The terminology used herein is for the purpose of describing particularaspects of the disclosure only, and is not intended to limit thedisclosure. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise.

FIG. 1 illustrates a contactless payment. FIG. 1 shows an arrangementcomprising a card reader terminal 10 and a contactless payment card 30.The card reader terminal 10 may be a traditional POS terminal or it maybe a so called mPos, i.e. a mobile point of sale.

A point of sale terminal, POS terminal, is an electronic device used toprocess card payments at retail locations. A POS terminal is generallyconfigured to read the information off a customer’s credit or debitcard. The card interface may be e.g. a chip card interface, a magneticstripe card reader or an interface for reading contactless cards usingNear Field Communication, NFC. Advanced POS terminals are typicallyequipped with a combination of these interfaces.

The POS typically also connects to an acquiring bank to check whetherthe funds in a customer’s bank account are sufficient or it decides thatthe transaction may be approved without checking the funds. The POS thentransfers the funds from the customer’s account to the seller’s accountor at least, accounts for the transfer with the credit card network. POSterminals may also be configured to record the transaction and toprovide a digital or printed receipt.

An mPos is e.g. a smartphone, tablet or dedicated wireless device thatperforms the functions of a cash register or electronic point of saleterminal.

Near Field Communication, NFC, is a standards-based connectivitytechnology that establishes wireless connection between two devices inclose proximity of each other (e.g., most commonly when the devices arewithin 0-4 centimetres from each other and theoretically the devices canbe up to 20 centimetres apart). NFC allows users to transfer informationby touching, or tapping, one device with another device. The act ofbringing one NFC-enabled device to close proximity of anotherNFC-enabled device with or without the two devices physically contactingeach other is referred to as “NFC bump” or “NFC tap” hereinafter. It mayalso be more generally called “bumping” or “tapping”.

The POS terminal in FIG. 1 comprises an interface for readingcontactless cards. The interface typically comprises an NFC antenna 11and an NFC controller (not shown). The NFC antenna in the POS terminalcommunicates with a NFC antenna 31 in the contactless card 30, wherebycredit card information required to perform an electronic payment suchas an EMV payment is exchanged, see EMV® Contactless Specifications forPayment Systems, Version 2.5 March 2015.

Hence, the operation of POS terminals is generally controlled bystandards such as PCI and already mentioned EMV. Payment Card Industry,PCI, Data Security Standard are technical and operational requirementsset by the PCI Security Standards Council, PCI SSC, to protectcardholder data. The PCI standards also define requirements forprotection of secure data in the POS terminal upon entry.

As discussed above, the traditional placement of the NFC antenna underthe upper side of a card reader terminal may cause trouble to the userwhen tapping the card, as the card reader may e.g. be out of reach ofthe customer. Hence, providing freedom to the merchant to place the NFCantenna in other places may be desirable. This may be accomplished byseparating the NFC antenna from the card reader terminal.

Published patent application US 2012/168504 A1 discloses two partcontactless readers comprising a base unit and a customer facing unit.The customer facing unit that may contain a contactless antenna, maye.g. be placed on a disk. The purpose of the teaching of is to overcomethe need for any direct connection between the customer-facing unit andthe base unit, as it may be desirable to place them e.g. on oppositesides of a counter.

The electronic circuitry in the base unit may be substantiallyconventional except that, in some embodiments, it may include structurefor inductive coupling to the customer-facing unit and/or for wirelesslytransmitting power to the customer-facing unit. However, such a solutionlimits the freedom of the merchant to place the units both in horizontaland vertical direction with regards to each other, because then theinductive coupling is lost.

US 2012/168504 A1 also presents an alternative solution where theelectronic components in the base unit may include one or more devicesfor implementing a radio or optical communications link to thecustomer-facing unit. With this solution the base unit may be separatedfrom the customer unit with a larger distance provided that a radio oroptical communications link is used. However, when using a radio oroptical communications link for transferring sensitive card data is asecurity risk, as the signal read from the contactless card needs to bedemodulated and decoded in the customer facing unit before is its sentto the base unit. Hence, additional encryption is required, whichrequires extra components and processing. In accordance with the PCIstandard the path of contactless data must be secured to 16 pointsattack potential from the point of digitisation of the data.

“Attack potential” is a term that appears often in the documentationpublished by the PCI Security Standards Council, PCI SSC. Attackpotential is a numeric value that refers to the security vulnerabilityof a given piece of equipment. The higher the number, the more securethe device.

In order to solve the need for additional security, and still keep thefreedom regarding how to position the antenna 21 in relation to the cardreader terminal 10 a secure arrangement is proposed. The principle,which is illustrated in FIG. 2 , is to provide the antenna in anexternal contactless card reader 20 which has a physical connection 40to the card reader terminal 10. The system then needs to be configuredsuch that signals received by the short distance antenna can propagateall the way to the card reader terminal, without intermediatedigitisation. Hence, digitisation takes place within a secured area inthe card reader terminal 10. In this way a simple solution is providedwhere no digital signal comprising card data is exposed, i.e., allowedto propagate without the possibility of being wire-tapped. Hence, theneed for additional encryption is avoided. The analogue signal providedby the antenna can easily be isolated. If the feed line is a coaxialcable then the analogue signal only propagates between the innerconductor and the tubular insulating layer. Hence, there is noadditional exposure of the signal transmitted by the contactless card,except at the transmission from the card, which is limited in time andplace.

One example is donations. It may be desirable to enable a customer tomake a donation using a contactless card. However, it can beinconvenient if the contactless tap zone is on the card reader, if thecard reader terminal is positioned out of reach of the customer. Forexample the donation may be given at entry/exit in a store, while thePOS reader might be located at the desk.

A contactless collection box may then be connected to a POS terminal. Insuch a case it is potentially desirable to have two or more shortdistance antennas working simultaneously. For example one short distanceantenna is positioned on the actual POS terminal and one on thecollection box.

The secure arrangement will now be further described referring to FIG. 3. The scenarios generally apply to situations when a merchant holds aPOS or mPOS terminal and the customer has a contactless card that is tobe tapped on the POS. As mentioned above, an object of the proposedtechnique is to implement an external antenna pad providing moreconvenience to customers to tap their contactless card that fulfilssecurity requirements with limited or no addition of cost.

FIG. 3 shows a secure arrangement for performing secure contactlesspayments. The secure arrangement comprises a card reader terminal 10, anexternal contactless card reader 20 and a feed line 40.

A contactless card or contactless smartcard is a smart card that usesradio signals to provide a wireless connection to a card reader, so thatno physical contact is necessary. Typically a contactless smart card hasdimensions of credit-card size. Its embedded integrated circuits canstore and sometimes process data and communicate with a terminal viaradio waves e.g. 13.56 MHz.

The card reader terminal 10 comprises a secure controller 17 configuredfor performing financial transactions, such as contactless payments. Oneexample is the EMV contactless payments in accordance with the EMVspecification (see www.emvco.com). For security reasons the securecontroller 17 is located in a secure area 19 within the card readerterminal 10. Thereby, sensitive information cannot be reached by anunauthorized person. Typically the secure area is tamper proof, whichmeans that the secure area is tamper resistant. Tamper resistance isresistance to tampering (intentional malfunction or sabotage) by eitherthe normal users of a product, package, or system or others withphysical access to it. Tamper resistance ranges from simple featureslike glue or epoxy to more complex devices that render themselvesinoperable or encrypt all data transmissions between individual chips,or use of materials needing special tools and knowledge. That is, tamperresistance is a protection against physical destruction as well asdestruction and interception of the stored data. One example is tampermeshes or active meshes, where the secure area is surrounded with wiresforming space-filling curve, wherein an alarm goes off if a wire isbroken or if two signals short together. Such a mesh also blocks signalsinside the secure area from inspection.

The antenna of the secure arrangement is provided in an external part,here referred to as an external contactless card reader 20, which isconnected to the card reader via a feed line 40. The externalcontactless card reader 20 can be put e.g. inside a sticker, which wouldallow the owner of the card reader to attach the antenna in a placewhich is convenient for the paying customer to reach. The antenna couldalso be part of a different construction, for example a stand whichprimary intention is to keep the external contactless card reader 20 inplace. Moreover, the external contactless card reader can be a mobile tothat extent that it can be moved closer to the customer to ease thetapping.

Hence, the external contactless card reader 20 comprises ashort-distance communication antenna 21 configured for converting anelectromagnetic signal comprising card data, received from a contactlesspayment card 30, into an analogue signal.

Short distance communication, as is the term that may be used herein,refers to an communication using signals that propagate a shortdistance, whereby communication is typically established by bringing thecommunicating devices in close vicinity e.g. within 10, 15 or 20 cmreach. A typical example is near field communication, NFC. In thisdisclosure, NFC will be used as an example. However, the teachingsshould not be considered limited thereto, but it must be consideredapplicable to other similar protocols as well.

The short-distance communication antenna is for example an NFC antenna.The short-distance communication antenna has a limited communicationrange. NFC, though, is very short-range, and work over distances of 5 cmat most. However, a general security feature of contactless cards isthat they should not transmit payment information further than 10 cmfrom a reader. However, it may be possible to pick up signals even atlarger distance e.g. up to 45 cm. The short-distance communicationantennas are often simple loops of wire, occupying as much surface areaas the device allows. The loops may be circular, square, and rectangularand are basically inductors that induce a magnetic field, which further(via mutual coupling) induces an analogue signal in the card reader’santenna when they are closely placed.

The feed line 40 is configured for transferring the analogue signalbetween the external contactless card reader 20 and the card readerterminal. A feed line is per definition is the cable or transmissionline that connects the antenna with the radio transmitter or receiver.In a receiving antenna it transfers the tiny radio voltage induced inthe antenna by the radio wave to the receiver. In order to carry radiocurrent efficiently, feed lines are made of specialized types of cablescalled transmission lines. The most widely used types of feed lines arecoaxial cable, twin-lead, ladder line, and at microwave frequencies,waveguide. The feed line is typically between 30 cm and 200 cm long andthereby enables the merchant to relatively freely place the tap zone ina desired place.

In accordance with the invention, the secure area in the card readerterminal comprises an analogue to digital A/D converter 151 fordigitizing the analogue signal to a digital signal that can be processedby the secure controller 17. One main concept is that the point ofdigitization occurs inside the secure area. Thus, the digital signal isnever present outside the secure area.

According to some aspects of the disclosure, the secure area of the cardreader terminal comprises a short distance receiver circuitry 15. Thereceiver circuitry 15 typically samples, demodulates and decodes areceived analogue signal. The A/D converter 151 is located inside theshort distance receiver circuitry 15.

For NFC payments the point of digitization of the signal comprising thecard information occurs when the data is processed by a NFC receivercircuitry, also called NFC controller, which is the part that convertsthe analogue signal to a digital signal. In order to comply withexisting standards for contactless payments the signal must be protectedto 16 points from the point of digitisation. Hence, the NFC controllerneeds to be placed within the secured area and a feedline such as acable is used to enable the signal to propagate into the secured area.

In order to transfer the tiny radio voltage induced in the antenna bythe radio wave to the receiver impedance matching may be used. Impedancematching is the practice of designing the input impedance of anelectrical load or the output impedance of its corresponding signalsource to maximize the power transfer or minimize signal reflection fromthe load. The impedance matching is e.g. performed by antenna matchingcircuits forming a matching network that takes into account theimpedance of source and load as well as the frequencies that are used.In the security arrangement of FIG. 3 antenna matching circuits 13a, 23may be positioned on both sides of the feedline.

According to some aspects, the external contactless card reader 20comprises at least one antenna matching circuit 23 positioned betweenthe short-distance communication antenna 21 and the A/D converter 151.This antenna matching circuit 23 is configured for matching frequencycharacteristics of the short-distance communication antenna 21 withfrequency characteristics of the feed line, or with frequencycharacteristics feed line in combination with frequency characteristicsof a connection point 51 of the feed line in the card readerterminal.According to some aspects, at least one antenna matchingcircuit 13a is placed in the card reader terminal 10. The matchingcircuit 13a is then adapted to match frequency characteristics of thefeed line 40 in combination with with frequency characteristics of aconnection point 52 of the feed line in the external contactless cardreader, with the frequency characteristics of a connection point 51 ofthe feed line in the card reader terminal.

In case of a long cable, the impedance of the connection point 51 of thefeed line in the card reader terminal may be negligible in relation tothe impedance of the feedline. Then the matching circuit 13a is adaptedto match the frequency characteristics of the feed line 40, with thefrequency characteristics of a connection point 51 of the feed line inthe card reader terminal.

As discussed above it may be desirable to be able to also use aninternal short distance antenna 11 in the card reader terminal 10. Theshort-distance communication antenna 21 in the external contactless cardreader 20 is then denoted “a first short-distance communication antenna21” The card reader terminal 10 then comprises a second short-distancecommunication antenna 11. It is then possible to use the same receivercircuitry 15 e.g. a NFC controller for both antennas. Hence, the firstand second short-distance communication antennas are both connected tothe short distance receiver circuitry 15.

A switch arrangement may be used for switching between the antennas.According to some aspects, card reader terminal 10 comprises a switcharrangement 14 configured to connect at least one of the first andsecond short-distance communication antennas to the receiver circuitry15. The switch arrangement is configured to enable none, one or severalconnected short distance antennas. One scenario is that both antennasare by default active, but that as soon as activity is detected at oneof the antennas the other one/or ones is automatically disabled.Alternatively the switch arrangement may be manually controlled by themerchant through hardware and/or software.

Furthermore, the second short-distance communication antenna may beequipped with a matching circuit 13 b. The input impedance in theconnection point 52 depends on the parameters of the feed line (e.g.,length and characteristic impedance) as well as the impedance of theload connected in the connection point 51, i.e., the card readerterminal 10. In the same manner the input impedance in the connectionpoint 52 depends on the parameters of the feed line and the impedance ofthe load connected in the connection point 51, i.e., the externalcontactless card reader 20.

In other words, according to some aspects, the card reader terminal 10comprises 20 at least one antenna matching circuit 13 b positionedbetween the internal short-distance communication antenna 11 and the A/Dconverter 151. The antenna matching circuit 13 b is for exampleconfigured to match frequency characteristics of the secondshort-distance communication antenna 21 with frequency characteristicsof a connection point 53 in the card reader terminal. The matchingcircuit 13 b is configured to match the impedance of the load of therespective sides of the matching circuit, wherein one load comprises atleast the second short-distance communication antenna 11 and the otherload comprises at least the switch arrangement 14 and the circuitry ofthe secure area 19.

With reference now made to FIG. 4 , illustrating schematically a sideview of the external contactless card reader 20 and its internalcomponents, the card reader 20 may comprise an electromagnetic shield 60to protect its internal circuitry, including at least the short-distancecommunication antenna 21, from magnetic and/or electromagneticinterference (EMI). EMI is basically disruptive electromagnetic energywhich, if reaching the antenna 21 or the matching circuit 23, maydisrupt proper operation of the external contactless card reader 20.

In particular, the electromagnetic shield 60 is configured to prevent orat least mitigate the negative effects otherwise caused by metalsurfaces in the immediate vicinity of the short-distance communicationantenna 21. When placed on or close to a metal surface, theshort-distance communication antenna 21 may generate eddy currents inthe metal surface, which eddy currents produce a magnetic flow thatcounteracts or disrupts the magnetic field of the antenna 21. To preventthis, the electromagnetic shield 60 of the external contactless cardreader 20 may comprise a metallic layer that shields the antenna 21 fromthe underlying surface to ensure that the metal environment of the cardreader 20 remains the same no matter where the card reader 20 is placedor located. Preferably, the electromagnetic shield 60 further comprisesa ferrite layer that shields the short-distance communication antenna 21from the metallic layer of the electromagnetic shield, so as to prevent“self-induced” eddy currents and disruptive magnetic flows from beingproduced by the metallic layer of the electromagnetic shield. Byadapting the short-distance communication antenna 21 and the matchingcircuit 23 to the metallic layer and the optional ferrite layer of theelectromagnetic shield 60, proper operation of the external contactlesscard reader 20 can be maintained also in metal environments.

In the embodiment illustrated in FIG. 4 , the external contactless cardreader 20 is substantially flat and may have a thickness in the range of0.5-5 mm. The card reader 20 has a bottom surface 62 that is intended torest on, or be attached to, an underlying surface 63, such as a surfaceof a table or a checkout counter, and a top surface 64 intended to facea user of the card reader 20, i.e. a cardholder that is about toinitiate a financial transaction by tapping the tap zone of the cardreader 20 using a contactless payment card 30. The shape and size of thecard reader 20 may vary in dependence of the intended use and locationof the card reader, and the requirements of the short-circuitcommunication antenna 21. In typical applications, the flat card reader20 may have a substantially circular or substantially rectangular shapewith a surface area in the range 1-100 cm2.

As illustrated in the drawing, the external contactless card reader 20may be a substantially flat, multi-layer construction comprising aplurality of substantially parallel layers or elements providing thedesired functionality of the card reader 20.

The main component of the contactless card reader 20 is an antenna layer66 comprising the short-distance communication antenna 21 and preferablyalso the antenna matching circuitry 23 (not shown). The short-distancecommunication antenna 21 is typically a loop antenna. As shown inprevious drawings, the short-distance communication antenna 21 of theantenna layer 66 is connected to the card reader terminal 10 via thephysical connection 40.

In this embodiment, the electromagnetic shield 60 is constituted by ashielding layer that is applied under the antenna layer 66, i.e. betweenthe antenna layer 66 and the bottom surface 62 of the card reader 20, toshield the antenna layer 66 from the underlying surface 63. Theelectromagnetic shield 60 comprises a metallic layer 60 a comprising anelectrically conductive metal. The metallic layer 60 a may, for example,comprise a metal sheet or a metal mesh. In one exemplary embodiment, themetallic layer 60 a comprises an aluminium foil. The metallic layer 60 ais preferably arranged to cover the entire short-distance communicationantenna 21, meaning that the antenna 21 is arranged inside, andpreferably well inside, the circumference of the metallic layer 60 a ina direction perpendicular to the layers of the card reader 20.

Furthermore, the electromagnetic shield 60 comprises a ferrite layer 60b, arranged between the antenna layer 66 and the metallic layer 60 a.The ferrite layer 60 b may, for example, be constituted by a ferritefoil. The properties of the ferrite of effectively conducting magneticflux while being a poor electrical conductor make the ferrite layer 60 bprevent eddy currents from arising in the metallic layer 60 a whileensuring proper operation of the short-distance communication antenna21. As illustrated in the drawing, the ferrite layer 60 b is alsoarranged to cover the entire short-distance communication antenna 21,meaning that the antenna 21 is arranged inside the circumference of theferrite layer 60 b in a direction perpendicular to the layers of thecard reader 20. Preferably, to effectively prevent eddy currents fromarising in the metallic layer 60 a, the antenna 21 should be arrangedentirely within the circumference of the ferrite layer 60 b in adirection perpendicular to the layers of the card reader, such that theferrite layer 60 b extends outside of the circumference of the antenna21. At the same time it has been found that the ferrite layer 60 bshould not extend too much outside of the circumference of the antenna21 since this may negatively effect antenna field distribution and thusprevent proper operation of the external contactless card reader 20. The“ferrite overhang”, i.e. the distance with which the ferrite layer 60 bextends outside the circumference of the antenna 21 as seen from adirection that is perpendicular to the antenna and ferrite layers, maydepend on the properties of the antenna 21, the metal layer 60 a and theferrite layer 60 b, but should preferably be within the range of 1-10mm. In some embodiments in which the short-distance communicationantenna 21 is an NFC loop antenna, an overhang of approximately 5 mm hasbeen found suitable.

Consequently, according to one aspect of the disclosure, the externalcontactless card reader 20 comprises a lower metallic layer 60 a, amiddle ferrite layer 60 b arranged on top of the metallic layer 60 a,and a top antenna layer 66 arranged on top of the ferrite layer 60 b,wherein the surface areas of the layers increase in the order from topto bottom to ensure proper operation of the short-distance communicationantenna 21. In this regard, the “surface area” of the antenna layerrefers to the surface area defined by the circumference of the antennacoil.

In the exemplary embodiment illustrated in FIG. 4 , the externalcontactless card reader 20 is realized in form of a flat antennasticker, e.g. an NFC reader sticker, and comprises an adhesive layer 68applied to the bottom surface of the shielding layer 60 in order for thecard reader 20 to be easily attached to the underlying surface 63. Inthis context it should be noted that the underlying surface 63 does notneed to be horizontal and that the external contactless card reader 20may be attached to virtually any surface. Also illustrated in thedrawing is an optional top layer 70 of the external contactless cardreader 20, provided on top of the antenna layer 66. The top layer 70may, for example, comprise a picture or a symbol indicating to thecardholder that this is the tap zone where the cardholder should tap hiscontactless payment card.

The components of the secure arrangement disclosed herein may alsocomprise additional components such as power amplifiers in order to e.g.enhance signal transfer.

Aspects of the disclosure are described with reference to the drawings,e.g., block diagrams and/or flowcharts. It is understood that severalentities in the drawings, e.g., blocks of the block diagrams, and alsocombinations of entities in the drawings, can be implemented by computerprogram instructions, which instructions can be stored in acomputer-readable memory, and also loaded onto a computer or otherprogrammable data processing apparatus. Such computer programinstructions can be provided to a processor of a general purposecomputer, a special purpose computer and/or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer and/or otherprogrammable data processing apparatus, create means for implementingthe functions/acts specified in the block diagrams and/or flowchartblock or blocks.

In some implementations and according to some aspects of the disclosure,the functions or steps noted in the blocks can occur out of the ordernoted in the operational illustrations. For example, two blocks shown insuccession can in fact be executed substantially concurrently or theblocks can sometimes be executed in the reverse order, depending uponthe functionality/acts involved. Also, the functions or steps noted inthe blocks can according to some aspects of the disclosure be executedcontinuously in a loop.

In the drawings and specification, there have been disclosed exemplaryaspects of the disclosure. However, many variations and modificationscan be made to these aspects without substantially departing from theprinciples of the present disclosure. Thus, the disclosure should beregarded as illustrative rather than restrictive, and not as beinglimited to the particular aspects discussed above. Accordingly, althoughspecific terms are employed, they are used in a generic and descriptivesense only and not for purposes of limitation.

It should be noted that although terminology from NFC has been usedherein to explain the example embodiments, this should not be seen aslimiting the scope of the example embodiments to only the aforementionedsystem. Other wireless systems may also benefit from the exampleembodiments disclosed herein.

The description of the example embodiments provided herein have beenpresented for purposes of illustration. The description is not intendedto be exhaustive or to limit example embodiments to the precise formdisclosed, and modifications and variations are possible in light of theabove teachings or may be acquired from practice of various alternativesto the provided embodiments. The examples discussed herein were chosenand described in order to explain the principles and the nature ofvarious example embodiments and its practical application to enable oneskilled in the art to utilize the example embodiments in various mannersand with various modifications as are suited to the particular usecontemplated. The features of the embodiments described herein may becombined in all possible combinations of methods, apparatus, modules,systems, and computer program products. It should be appreciated thatthe example embodiments presented herein may be practiced in anycombination with each other.

It should be noted that the word “comprising” does not necessarilyexclude the presence of other elements or steps than those listed andthe words “a” or “an” preceding an element do not exclude the presenceof a plurality of such elements. It should further be noted that anyreference signs do not limit the scope of the claims, that the exampleembodiments may be implemented at least in part by means of bothhardware and software, and that several “means”, “units” or “devices”may be represented by the same item of hardware.

In the drawings and specification, there have been disclosed exemplaryembodiments. However, many variations and modifications can be made tothese embodiments. Accordingly, although specific terms are employed,they are used in a generic and descriptive sense only and not forpurposes of limitation, the scope of the embodiments being defined bythe following claims.

1-14. (canceled)
 15. An apparatus, comprising: an external contactlesscard reader that includes a first short-distance communication antennaconfigured to convert an electromagnetic signal that includes card data,received from a contactless payment card, into an analog signal, whereinthe external contactless card reader is not configured to digitize theanalog signal; and a card reader terminal that is connected to theexternal contactless card reader using a feed line, wherein the cardreader terminal includes: a secure area within the card reader terminal;a short-distance receiver circuit located in the secure area within thecard reader terminal, wherein the short-distance receiver circuit isconfigured to convert the analog signal, received via the feed line fromthe external contactless card reader, to a digital signal; a securecontroller located in the secure area within the card reader terminal,wherein the secure controller is configured to perform a financialtransaction based on the card data included in the digital signal; and asecond short-distance communication antenna, wherein the first andsecond short-distance communication antennas are connected via separatepaths to the short-distance receiver circuit.
 16. The apparatus of claim15, further comprising a first antenna matching circuit positionedbetween the first short-distance communication antenna and theshort-distance receiver circuit.
 17. The apparatus of claim 16, whereinthe first antenna matching circuit is within the external contactlesscard reader.
 18. The apparatus of claim 17, wherein the first antennamatching circuit is configured to match frequency characteristics of thefirst short-distance communication antenna with at least one of:frequency characteristics of the feed line configured to transfer theanalog signal from the external contactless card reader to the cardreader terminal; or frequency characteristics of the feed line incombination with frequency characteristics of a connection point of thefeed line in the card reader terminal.
 19. The apparatus of claim 16,wherein the first antenna matching circuit is within the card readerterminal.
 20. The apparatus of claim 19, wherein the first antennamatching circuit is configured to match frequency characteristics of aconnection point of the feed line in the card reader terminal with acombination of the feed line and a connection point of the feed line inthe external contactless card reader.
 21. The apparatus of claim 15,wherein the card reader terminal further includes a switch arrangementconfigured to select one of the first or second short-distancecommunication antennas for connection to the short-distance receivercircuit.
 22. The apparatus of claim 15, wherein the card reader terminalincludes a second antenna matching circuit positioned between the secondshort-distance communication antenna and the short-distance receivercircuit, wherein the second antenna matching circuit is configured tomatch frequency characteristics of the second short-distancecommunication antenna with frequency characteristics of a connectionpoint in the card reader terminal.
 23. The apparatus of claim 15,wherein the feed line is a twin-lead cable or a coaxial cable.
 24. Theapparatus of claim 15, wherein the feed line is between 30 cm and 200 cmlong.
 25. The apparatus of claim 15, wherein the second short-distancecommunication antenna is a Near-Field Communication antenna.
 26. Theapparatus of claim 15, wherein the second short-distance communicationantenna has a communication range of up to 10 cm.
 27. The apparatus ofclaim 15, wherein the secure area is tamper proof.
 28. The apparatus ofclaim 27, wherein the secure area is surrounded by a tamper mesh thatincludes electrically conductive traces.
 29. A method, comprising:receiving, via a first short-distance communication antenna in anexternal contactless card reader, an electromagnetic signal thatincludes card data from a contactless payment card; converting, by thefirst short-distance communication antenna, the electromagnetic signalinto an analog signal; and transferring the analog signal from theexternal contactless card reader to a card reader terminal withoutdigitizing the analog signal at any point between the firstshort-distance communication antenna and the card reader terminal,wherein the card reader terminal is connected to the externalcontactless card reader via a feed line, and wherein the card readerterminal includes: a secure controller, located in a secure area withinthe card reader terminal, configured to perform financial transactions;a short-distance receiver circuit, located in the secure area within thecard reader terminal, wherein the short-distance receiver circuit isconfigured to convert the analog signal to a digital signal that can beprocessed by the secure controller; and a second short-distancecommunication antenna, wherein the first and second short-distancecommunication antennas are connected via separate paths to theshort-distance receiver circuit.
 30. The method of claim 29, wherein thesecond short-distance communication antenna is within the card readerterminal.
 31. The method of claim 29, further comprising matching, by afirst antenna matching circuit positioned between the firstshort-distance communication antenna and the short-distance receivercircuit, one or more frequency characteristics of the firstshort-distance communication antenna with frequency characteristics ofthe feed line.
 32. The method of claim 29, wherein the card readerterminal further includes a switch arrangement configured to select oneof the first or second short-distance communication antennas forconnection to the short-distance receiver circuit.
 33. The method ofclaim 29, further comprising matching, by a second antenna matchingcircuit positioned between the second short-distance communicationantenna and the short-distance receiver circuit, one or more frequencycharacteristics of the second short-distance communication antenna withfrequency characteristics of a connection point in the card readerterminal.
 34. A method, comprising: receiving, at a short-distancereceiver circuit located in a secure area of a card reader terminal, ananalog signal from one of a first short-distance communication antennaor a second short-distance communication antenna, wherein: the firstshort-distance communication antenna is located in an externalcontactless card reader; the external contactless card reader isconfigured to transfer the analog signal to the card reader terminalwithout digitizing the analog signal; the external contactless cardreader is connected to the card reader terminal via a feed line; and thefirst and second short-distance communication antennas are connected viaseparate paths to the short-distance receiver circuit; converting, bythe short-distance receiver circuit, the analog signal to a digitalsignal; and performing, by a secure controller located in the securearea, a financial transaction based on card data included in the digitalsignal, wherein the card data is received by the first or secondshort-distance communication antenna from a contactless payment card.